Chokidar CLI
Fast cross-platform command line utility to watch file system changes.
The underlying watch library is Chokidar, which is one of the best watch utilities for Node. Chokidar is battle-tested:
It is used in
brunch,
gulp,
karma,
PM2,
browserify,
webpack,
BrowserSync,
socketstream,
derby,
and many others.
It has proven itself in production environments.
Prerequisites
Install
If you need it only with npm scripts:
npm install chokidar-cli
Or globally
npm install -g chokidar-cli
Usage
Chokidar can be invoked using the chokidar command, without the -cli suffix.
Arguments use the form of runtime flags with string parameters, delimited by quotes. While in principal both single and double quotes are supported by chokidar-cli, the actual command line argument parsing is dependent on the operating system and shell used; for cross-platform compatibility, use double quotes (with escaping, if necessary), as single quotes are not universally supported by all operating systems.
This is particularly important when using chokidar-cli for run scripts specified in package.json. For maximum platform compatibility, make sure to use escaped double quotes around chokidar's parameters:
"run": {
"chokidar": "chokidar \"**/*.js\" -c \"...\""
},
Default behavior
By default chokidar streams changes for all patterns to stdout:
$ chokidar "**/*.js" "**/*.less"
change:test/dir/a.js
change:test/dir/a.less
add:test/b.js
unlink:test/b.js
Each change is represented with format event:relativepath. Possible events: add, unlink, addDir, unlinkDir, change.
Output only relative paths on each change
$ chokidar "**/*.js" "**/*.less" | cut -d ":" -f 2-
test/dir/a.js
test/dir/a.less
test/b.js
test/b.js
Run npm run build-js whenever any .js file changes in the current work directory tree
chokidar "**/*.js" -c "npm run build-js"
Watching in network directories must use polling
chokidar "**/*.less" -c "npm run build-less" --polling
Pass the path and event details in to your custom command
chokidar "**/*.less" -c "if [ '{event}' = 'change' ]; then npm run build-less -- {path}; fi;"
Detailed help
Usage: chokidar <pattern> [<pattern>...] [options]
<pattern>:
Glob pattern to specify files to be watched.
Multiple patterns can be watched by separating patterns with spaces.
To prevent shell globbing, write pattern inside quotes.
Guide to globs: https://github.com/isaacs/node-glob#glob-primer
Options:
-c, --command Command to run after each change. Needs to be
surrounded with quotes when command contains spaces.
Instances of `{path}` or `{event}` within the command
will be replaced by the corresponding values from the
chokidar event.
-d, --debounce Debounce timeout in ms for executing command
[default: 400]
-t, --throttle Throttle timeout in ms for executing command
[default: 0]
-s, --follow-symlinks When not set, only the symlinks themselves will be
watched for changes instead of following the link
references and bubbling events through the links path
[boolean] [default: false]
-i, --ignore Pattern for files which should be ignored. Needs to be
surrounded with quotes to prevent shell globbing. The
whole relative or absolute path is tested, not just
filename. Supports glob patterns or regexes using
format: /yourmatch/i
--initial When set, command is initially run once
[boolean] [default: false]
-p, --polling Whether to use fs.watchFile(backed by polling) instead
of fs.watch. This might lead to high CPU utilization.
It is typically necessary to set this to true to
successfully watch files over a network, and it may be
necessary to successfully watch files in other non-
standard situations [boolean] [default: false]
--poll-interval Interval of file system polling. Effective when --
polling is set [default: 100]
--poll-interval-binary Interval of file system polling for binary files.
Effective when --polling is set [default: 300]
--verbose When set, output is more verbose and human readable.
[boolean] [default: false]
--silent When set, internal messages of chokidar-cli won't be
written. [boolean] [default: false]
-h, --help Show help [boolean]
-v, --version Show version number [boolean]
Examples:
chokidar "**/*.js" -c "npm run build-js" build when any .js file changes
chokidar "**/*.js" "**/*.less" output changes of .js and .less
files
License
MIT
